login
The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A048547 a(n) is the smallest value of m such that A002378(m), the m-th oblong number, contains exactly n 9's. 10
9, 31, 890, 2234, 14131, 30331, 173031, 969520, 9958890, 31617890, 360542549, 547631234, 3316547890, 17318486343, 114017542334, 356363452109, 3065925634968 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..17.

Eric Weisstein's World of Mathematics, Pronic Number

EXAMPLE

From Jesse Sealand, Oct 07 2019: (Start)

a(1) = 9 since A002378(9) = 90;

a(2) = 31 since A002378(31) = 992;

a(3) = 890 since A002378(890) = 792990;

a(4) = 2234 since A002378(2234) = 4992990, etc.

(End).

CROSSREFS

Cf. A048548, A002378.

Cf. A048529, A048531, A048533, A048535, A048537, A048539, A048541, A048543, A048545.

Sequence in context: A177743 A266710 A159279 * A141573 A075433 A018833

Adjacent sequences:  A048544 A048545 A048546 * A048548 A048549 A048550

KEYWORD

nonn,base,more

AUTHOR

Patrick De Geest, May 15 1999

EXTENSIONS

a(13)-a(16) from Lars Blomberg, Jun 10 2011

Name edited by Jesse Sealand, Oct 07 2019

a(17) from Giovanni Resta, Oct 09 2019

STATUS

approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified July 10 14:17 EDT 2020. Contains 335576 sequences. (Running on oeis4.)